/Engine/Source/Editor/StaticMeshEditor/Public/StaticMeshEditorSubsystem.h
Same as SetConvexDecompositionCollisionsWithNotification but changes are automatically applied.
bool SetConvexDecompositionCollisions ( [UStaticMesh](API\Runtime\Engine\Engine\UStaticMesh) * StaticMesh, int32 HullCount, int32 MaxHullVerts, int32 HullPrecision )